The civil suit allegations are by a former employee of Harrah's hotel-casino, who says the attack occurred there in July 2008. Andrea McNulty says the attack happened to her when the Super Bowl-winning quarterback was in Tahoe playing in a celebrity golf tournament. She also alleges that Harrah's officials refused to investigate her complaint and went to great lengths to cover up the incident.

But the NFL star's lawyer told NBC Sports that the charges by McNulty are false. "Ben has never sexually assaulted anyone, especially Andrea McNulty," said David Cornwell.

The civil suit, filed last week in Washoe County, Nevada, claims Roethlisberger asked McNulty to come to his hotel room to fix the television. Once she arrived, McNulty alleges, he forced her to have sex with him. Roethlisberger faces several civil charges, including assault, sexual assault and battery, and intentional infliction of emotional distress.

(AP Photo/Chris Carlson)

No criminal complaint has been filed.

"The timing of the lawsuit and the absence of a criminal complaint and a criminal investigation are the most compelling evidence of the absence of any criminal conduct," Cornwell said.

"If an investigation is commenced, Ben will cooperate fully and Ben will be fully exonerated."

Steelers spokesman Dave Lockett said Tuesday the team is aware of the lawsuit, and "we are gathering information."